scholarly journals Effect of vegetation suppression on the establishment of sod-seeded alfalfa in the Aspen Parkland

1992 ◽  
Vol 72 (4) ◽  
pp. 1349-1358 ◽  
Author(s):  
G. G. Bowes ◽  
R. P. Zentner
Keyword(s):  
Populus Tremuloides ◽  
Net Present Value ◽  
Low Cost ◽  
Economic Assessment ◽  
Populus Balsamifera ◽  
Forage Grasses ◽  
Smooth Bromegrass ◽  
East Central ◽  
Aspen Parkland ◽  
Forage Yields

Four trials were conducted on a heavily grazed bluegrass-dominated pasture located in east-central Saskatchewan to compare the establishment of alfalfa (Medicago media Pers. Drylander) and forage grasses with no suppression vs. suppression of the resident vegetation using either glyphosate or rotovation. Successful forage establishment was based on seedling count, herbage yield and an economic assessment using net present value. The test area had been cleared of mature aspen poplar (Populus tremuloides Michx.) and balsam poplar (Populus balsamifera L.) trees, treated with 2,4-D to control suckering and was subsequently invaded by native forbs and grasses, mainly bluegrasses. Alfalfa successfully established with or without suppression while smooth bromegrass (Bromus inermis Leyss. ’Carlton’) established only when a suppression treatment was applied. Forage yields, averaged over 4 yr and four trials, following sod-seeding and glyphosate at 2.5 kg ha−1 were 1973 and 612 kg ha−1 for alfalfa and bluegrass plus smooth bromegrass, compared to 1287 and 748 kg ha−1 for alfalfa and bluegrass plus smooth bromegrass, respectively, when there was no suppression of the resident vegetation. The low-cost, no-suppression sod-seeding treatment was as profitable as the sod-seeding treatment using glyphosate.Key words: Sod-seed, zero till, alfalfa, smooth bromegrass, economics, glyphosate

Economics of chemical brush control in pastures of east-central Saskatchewan

1991 ◽  
Vol 71 (4) ◽  
pp. 1133-1141
Author(s):  
R. P. Zentner ◽  
G. G. Bowes
Keyword(s):  
Discount Rate ◽  
Populus Tremuloides ◽  
Net Present Value ◽  
Dry Weight ◽  
Control Treatment ◽  
Discount Rates ◽  
Economic Returns ◽  
East Central ◽  
Brush Control ◽  
Growing Conditions

The economic merit of controlling brush regrowth using combinations of 2,4-D and dicamba with different patterns of repeat applications was assessed for pastures in east-central Saskatchewan. Two experiments were conducted simultaneously in a community pasture located on a Waitville loam. The area, which was originally dominated by aspen poplar (Populus tremuloides Michx.), had been cleared of trees and shrubs by bulldozing before the start of the tests. In the first experiment started in 1981, 2,4-D ester plus dicamba and 2,4-D amine plus dicamba were foliar applied to the brush regrowth. Single applications were compared with repeat sprayings in the first, second, or in both years following the initial herbicide application. A subset of these treatments was used in a second experiment started in 1983 to determine whether or not productivity effects were influenced by growing conditions in the initial year of spraying. Herbicides effectively controlled brush regrowth which increased yields of useable herbage (grasses plus forbs) by an average of 32–39%. The forage benefits did not decline with time to the end of the study in 1989. Herbicide treatments were generally more profitable when applied to younger stands of brush regrowth, with the 2,4-D ester formulations being more profitable than 2,4-D amine formulations. Economic returns were highest, although not always positive, for the treatment receiving a one-time application of 2-4-D ester at 2.2 kg ha−1 plus dicamba at 1.5 kg ha−1 for forage values between $25 and $75 t−1 (dry weight) and discount rates between 0 and 10%. In order to justify this treatment cost, the minimum value that must be obtained when utilizing the additional forage was $20 t−1 (dry weight) for the most profitable control treatment, assuming a 5% discount rate and persistance of the treatment effects for up to 18 yr. For the other treatments, breakeven forage values ranged between $37 and 70 t−1 under similar assumptions. Higher discount rates or a shorter effective treatment life increased breakeven forage values. Repeat herbicide applications could not be justified under any of the economic scenarios. Key words: Net present value, benefit-cost ratios, discount rate, aspen poplar, herbicides, 2,4-D

scholarly journals Effects of annual burning on grassland in the aspen parkland of east-central Alberta

1980 ◽  
Vol 58 (8) ◽  
pp. 985-996 ◽  
Author(s):  
Howard G. Anderson ◽  
Arthur W. Bailey
Keyword(s):  
Populus Tremuloides ◽  
Forest Cover ◽  
Woody Species ◽  
Early Spring ◽  
Cool Season ◽  
Prunus Virginiana ◽  
East Central ◽  
Aspen Parkland ◽  
Calamovilfa Longifolia ◽  
Cool Season Grass

Annual early spring burning has markedly altered the physiognomy and species composition of aspen parkland vegetation of east-central Alberta. Burning was conducted in April for at least 24 years when soil moisture was normally high. The number of herbaceous species per quadrat doubled while a number of woody species declined slightly. Forest cover declined while grassland increased. In the grass and shrublands, cover of the shrub Symphoricarpos occidentalis and the cool season grass Festuca scabrella declined greatly. Major increases in Calamovilfa longifolia, Carex obtusata, C. heliophylla, and Solidago missouriensis were noted. While the cover of Festuca scabrella and Stipa spartea var. curtiseta decreased; frequency of these species increased. Cover of all shrubs decreased, Populus tremuloides suckers excepted, while density of the fire adapted Elaeagnus commutata, Amelanchier alnifolia, Prunus virginiana, and Populus tremuloides suckers increased. Burning reduced the leaf blade length of all major grasses and sedges. Effect of burning on inflorescence production varied from species to species. Annual herbage production was reduced by burning with the grass and sedge component experiencing about a 50% reduction. Burning caused an increase in organic matter and phosphorus content of the Ah horizon. Burning did not appear to detrimentally affect the nitrogen status of the Ah horizon.

scholarly journals Techno-Economic Assessment of Coal-Fired Power Unit Decarbonization Retrofit with KP-FHR Small Modular Reactors

Energies ◽  
2021 ◽  
Vol 14 (9) ◽  
pp. 2557
Author(s):  
Łukasz Bartela ◽  
Paweł Gładysz ◽  
Charalampos Andreades ◽  
Staffan Qvist ◽  
Janusz Zdeb
Keyword(s):  
Net Present Value ◽  
Economic Assessment ◽  
Plant Design ◽  
Term Operation ◽  
Small Modular Reactors ◽  
Greenfield Investments ◽  
Unit Design ◽  
The Difference ◽  
Economic Analyses ◽  
The Eu

The near and mid-term future of the existing Polish coal-fired power fleet is uncertain. The longer-term operation of unabated coal power is incompatible with climate policy and is economically challenging because of the increasing price of CO2 emission allowances in the EU. The results of the techno-economic analysis presented in this paper indicate that the retrofit of existing coal-fired units, by means of replacing coal-fired boilers with small modular reactors, may be an interesting option for the Polish energy sector. It has been shown that the retrofit can reduce the costs in relation to greenfield investments by as much as 35%. This analysis focuses on the repowering of a 460 MW supercritical coal-fired unit based on the Łagisza power plant design with high temperature small modular nuclear reactors based on the 320 MWth unit design by Kairos Power. The technical analyses did not show any major difficulties in integrating. The economic analyses show that the proposed retrofits can be economically justified, and, in this respect, they are more advantageous than greenfield investments. For the base economic scenario, the difference in NPV (Net Present Value) is more favorable for the retrofit by 556.9 M€ and the discounted payback period for this pathway is 10 years.

Effects of open-range cattle grazing on deciduous tree regeneration, damage, and mortality following patch logging

2014 ◽  
Vol 44 (7) ◽  
pp. 777-783 ◽  
Author(s):  
Jillian Kaufmann ◽  
Edward W. Bork ◽  
Michael J. Alexander ◽  
Peter V. Blenis
Keyword(s):  
Populus Tremuloides ◽  
Sustainable Forest Management ◽  
Deciduous Forest ◽  
Total Mortality ◽  
Cattle Grazing ◽  
Tree Regeneration ◽  
Deciduous Tree ◽  
Populus Balsamifera ◽  
Haul Road ◽  
The Impact

The impact of summer cattle grazing on deciduous tree regeneration within uncut forests, clearcuts, partially harvested areas, and in-block haul road habitats was examined in four experimental pastures of central Alberta during 2008 and 2009. Sampling of 233 field plots, both inside and outside cattle exclosures, was used to document sapling densities, height, and type of damage. Tree densities (primarily aspen (Populus tremuloides Michx.)) differed among habitats but less so with exposure to cattle. Densities were greatest in clearcuts, followed by partially harvested areas and then uncut forest and haul roads. While exposure to cattle reduced total tree regeneration, sapling densities and sizes remained sufficient to meet postharvest standards for deciduous forest regeneration in Alberta, even with exposure to cattle. Cattle damage in harvested areas was primarily from browsing (≤3.2% of saplings), with proportionally more trees affected in uncut forests (8.6%). Browsing was particularly high on balsam poplar (Populus balsamifera L.) (25%) during 2008. Although sapling damage increased with high cattle stocking in 2008 (to 10.5%), total mortality was limited to 15.5% through 2009. These findings show that despite cattle impacts to some saplings, damage levels were insufficient to alter deciduous regeneration, highlighting the compatibility of cattle grazing and sustainable forest management on public lands in this region.

scholarly journals Economic Assessment of Technology Adoption in Oil Palm Plantations from Colombia

2017 ◽  
Vol 8 (3) ◽  
pp. 74 ◽  
Author(s):  
Mauricio Mosquera-Montoya ◽  
Elizabeth Ruiz-Alvarez ◽  
Eloina Mesa-Fuquen
Keyword(s):  
Technology Adoption ◽  
Oil Palm ◽  
Net Present Value ◽  
Unit Cost ◽  
Economic Assessment ◽  
Net Income ◽  
Adoption Of Technology ◽  
Land Use Efficiency ◽  
Fresh Fruit Bunches ◽  
The One

Adopting technology regarding agricultural crops has traditionally been associated with high costs. Producers have thus often abstained from adopting better agronomical practices and have consequently lost the benefits they could otherwise have obtained by implementing better criteria for managing their crops.This research builds on results by Ruiz et al., (2017) who found three typologies of oil palm lots, regarding adoption of technology and yields on oil palm crops from Colombia. This work was aimed at evaluating the typologies found by Ruiz et al. (2017) from an economic standpoint by using different economic assessment methods, in order to determine the benefits of technology adoption at the Colombian oil palm agroindustry. The methods used were aimed at estimating: unit cost, net present value (NPV), net income, land use efficiency, generation of income and competitiveness.Results indicate that the cost of producing a ton of fresh fruit bunches from oil palms (FFB) on lots having high adoption of technology was 2.5% to 8% lower when compared to lots having lower adoption of technology (Typologies 2 and 3. respectively). Technology adoption enables greater yearly net income to be obtained in mature oil palm crops in typology 1, than the one obtained at typology 2 and typology 3. The adoption of technology allows the grower to obtain net income equivalent to a legally-established yearly minimum wage (LEYMW), using less land. Finally, it was concluded that at average CPO prices for the period 2005-2015, the Colombian growers that participated in this study, may be competitive at the European market, which is the main destination of Colombian exports of crude palm oil (CPO).

LNG Use in Freight Rail Industry as an Economic and Environmental Driver: A Technical, Operational and Economic Assessment

2017 ◽  
Author(s):  
Fábio C. Barbosa
Keyword(s):  
United States ◽  
Natural Gas ◽  
Alternative Fuels ◽  
Low Cost ◽  
Critical Evaluation ◽  
Economic Assessment ◽  
Environmental Benefits ◽  
Rail Freight ◽  
Emission Standards ◽  
Rail Industry

Freight rail carriers have been continuously challenged to reduce costs and comply with increasingly stringent environmental standards, into a continuously competing and environmentally driven industry. In this context, current availability and relative abundance of clean and low cost non conventional gas reserves have aroused a comprehensive reevaluation of rail industry into fuel option, especially where freight rail are strongly diesel based. Countries in which rail sector is required to play an important role in transport matrix, where fuel expenditures currently accounts for a significant share of operational costs, like Australia, Brazil, United States and other continental countries, can be seen as strong candidates to adopt fuel alternatives to diesel fueled freight railways. Moreover, from an environmental perspective, the use of alternative fuels (like natural gas) for locomotive traction may allow rail freight carriers to comply with emission standards into a less technologically complex and costly way. In this context, liquefied natural gas (LNG) fueled freight locomotives are seen as a strong potential near-term driver for natural gas use in rail sector, with its intrinsic cost and environmental benefits and with the potential to revolutionize rail industry much like the transition from steam to diesel experienced into the fifties, as well as the more recent advent of use of alternating current diesel-electric locomotives. LNG rail fueled approach has been focused on both retrofitting existing locomotive diesel engines, as well as on original manufactured engines. Given the lower polluting potential of natural gas heavy engines, when compared to diesel counterparts, LNG locomotives can be used to comply with increasingly restrictive Particulate Matter (PM) and Nitrogen Oxides (NOx) emission standards with less technological complexity (engine design and aftertreatment hardware) and their intrinsic lower associated costs. Prior to commercial operation of LNG locomotives, there are some technical, operational and economic hurdles that need to be addressed, i.e. : i) locomotive engine and fuel tender car technological maturity and reliability improvement; ii) regulation improvement, basically focused on operational safety and interchange operations; iii) current and long term diesel - gas price differential, a decisive driver, and, finally, iv) LNG infrastructure requirements (fueling facilities, locomotives and tender car specifications). This work involved an extensive research into already published works to present an overview of LNG use in freight rail industry into a technical, operational and economical perspective, followed by a critical evaluation of its potential into some relevant freight rail markets, such as United States, Brazil and Australia, as well as some European non electrified rail freight lines.

scholarly journals New distribution records for amphibians and reptiles in eastern Chihuahua, Mexico

Check List ◽  
2019 ◽  
Vol 15 (1) ◽  
pp. 79-86
Author(s):  
Tomas Hernandez ◽  
Mark W. Herr ◽  
Skyler Stevens ◽  
Karlee Cork ◽  
Carolina Medina-Nava ◽  
...  
Keyword(s):  
United States ◽  
Low Cost ◽  
Southwestern United States ◽  
High Quality ◽  
East Central ◽  
Northern Mexico ◽  
Reptile Species ◽  
Distributional Information ◽  
New Distribution

Distributions of amphibian and reptile species in northern Mexico are poorly understood when compared to adjacent areas of the southwestern United States. To address this gap in knowledge, we conducted a series of surveys in east-central Chihuahua, Mexico in 2014–2016. We documented 40 new municipality records for amphibian and reptile species by means of high quality digital photos. Photographic surveys offer a low-cost, highly accessible technique for accumulating distributional information.

scholarly journals Foliar Penetration of Picloram and 2,4-D in Aspen and Balsam Poplar

Weed Science ◽  
1970 ◽  
Vol 18 (1) ◽  
pp. 57-63 ◽  
Author(s):  
M. P. Sharma ◽  
W. H. Vanden Born
Keyword(s):  
Relative Humidity ◽  
Populus Tremuloides ◽  
High Relative Humidity ◽  
Populus Balsamifera ◽  
Cuticular Waxes ◽  
Adaxial Surface ◽  
Balsam Poplar ◽  
Detached Leaves ◽  
Young Leaves ◽  
Dichlorophenoxy Acetic Acid

Added surfactant (Atlox 210) at 1% (v/v) and high relative humidity enhanced the penetration of both 4-amino-3,5,6-trichloropicolinic acid (picloram) and (2,4-dichlorophenoxy)acetic acid (2,4-D) into detached leaves of aspen poplar (Populus tremuloides Michx.). The influence of added surfactant was greater for picloram and the dimethylamine of 2,4-D than for the ethyl or butoxyethanol ester of 2,4-D. Penetration of picloram and the dimethylamine of 2,4-D occurred more readily from the abaxial than from adaxial surfaces of leaves. The ethyl ester of 2,4-D penetrated equally readily from both leaf surfaces. Penetration of picloram and the dimethylamine of 2,4-D from the adaxial surface of leaves occurred readily in young leaves in early June. There was an increase in penetration in early July followed by a decrease in August and September to a level equal to or less than that in June. Penetration from the abaxial surface of leaves was nearly equal in June and July, but there was a gradual decrease in August and September. An increase in temperature from 10 to 25.5 or to 40.5 C resulted in a sharp increase in penetration of both picloram and 2,4-D under both low and high relative humidity. Autoradiographic evidence showed that movement of picloram within the leaf also was much more extensive at the higher temperatures. Partial removal of cuticular waxes from the adaxial surface of leaves with chloroform resulted in up to four-fold increases in penetration of picloram and 2,4-D. Differences in penetration rate of picloram between leaves of aspen poplar and balsam poplar (Populus balsamifera L.) did not account for reported differences in susceptibility between these two species.

scholarly journals Economic Conditions for Developing Hydrogen Production Based on Coal Gasification with Carbon Capture and Storage in Poland

Energies ◽  
2020 ◽  
Vol 13 (19) ◽  
pp. 5074
Author(s):  
Radosław Kaplan ◽  
Michał Kopacz
Keyword(s):  
Carbon Capture ◽  
Coal Gasification ◽  
Net Present Value ◽  
Carbon Capture And Storage ◽  
Economic Assessment ◽  
Free Cash Flow ◽  
Sensitivity Analyses ◽  
Capital Expenditures ◽  
Hard Coal ◽  
And Storage

This study documents the results of economic assessment concerning four variants of coal gasification to hydrogen in a shell reactor. That assessment has been made using discounting methods (NPV: net present value, IRR: internal rate of return), as well as indicators based on a free cash flow to firm (FCFF) approach. Additionally, sensitivity analysis has been carried out, along with scenario analysis in current market conditions concerning prices of hard coal, lignite, hydrogen and CO2 allowances, as well as capital expenditures and costs related to carbon capture and storage (CCS) systems. Based on NPV results, a negative economic assessment has been obtained for all the analyzed variants varying within the range of EUR −903 to −142 million, although the variants based on hard coal achieved a positive IRR (5.1–5.7%) but lower than the assumed discount rates. In Polish conditions, the gasification of lignite seems to be unprofitable, in the assumed scale of total investment outlays and the current price of coal feedstock. The sensitivity analyses indicate that at least a 20% increase of hydrogen price would be required, or a similar reduction of capital expenditures (CAPEX) and costs of operation, for the best variant to make NPV positive. Analyses have also indicated that on the economic basis, only the prices of CO2 allowances exceeding EUR 40/Mg (EUR 52/Mg for lignite) would generate savings due to the availability of CCS systems.

scholarly journals Plasma Assisted Combustion as a Cost-Effective Way for Balancing of Intermittent Sources: Techno-Economic Assessment for 200 MWel Power Unit

Energies ◽  
2020 ◽  
Vol 13 (19) ◽  
pp. 5056
Author(s):  
Tadeusz Mączka ◽  
Halina Pawlak-Kruczek ◽  
Lukasz Niedzwiecki ◽  
Edward Ziaja ◽  
Artur Chorążyczewski
Keyword(s):  
Power Unit ◽  
Net Present Value ◽  
Renewable Energy Sources ◽  
Cost Effective ◽  
Economic Assessment ◽  
Marginal Effect ◽  
The European Union ◽  
Present Value ◽  
Plasma System ◽  
Value Analysis

Due to the increasing installed power of the intermittent renewable energy sources in the European Union, increasing the operation flexibility of the generating units in the system is necessary. This is particularly important for systems with relatively large installed power of wind and solar. Plasma technologies can be used for that purpose. Nonetheless, the wide implementation of such technology should be economically justified. This paper shows that the use of plasma systems for increasing the flexibility of power units can be economically feasible, based on the results of a net present value analysis. The cost of the installation itself had a marginal effect on the results of the net present value analysis. Based on the performed analysis, the ability to lower the technical minimum of the power unit and the relationship between such a technical minimum and the installed power of a plasma system can be considered decisive factors influencing the economics of the investment for such an installation. Further research on better means of prediction of the minimum attainable load, which would allow determining the influence of implementation of a plasma system, is recommended. This will be the decisive factor behind future decisions regarding investing in such systems.

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